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Finding the Fourth Proportional to 279.09, 418.65 and 84.11

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Solution

The fourth proportional to 279.09, 418.65 and 84.11 is: 126.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.09 : 418.65 = 84.11 : x
  2. Step 2: Convert to fraction form
    279.09/418.65 = 84.11/x
  3. Step 3: Cross multiply
    279.09x = 418.65 × 84.11
  4. Step 4: Simplify right side
    279.09x = 35,210.56
  5. Step 5: Solve for x
    x = 35,210.56/279.09
  6. Step 6: Final answer
    x = 126.16

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.